Scrounger’s Guide - Vintage Stromberg Carbs

1/15The Stromberg 97 and its variants are the most popular nostalgia hot rod carburetor for multi-carb setups. The advantage to these over the also-common Holley 94s is the brass power valve is mechanical while the 94 uses a vacuum diaphragm. There are a multitude of slight casting differences throughout the run of 97s and their variants, which include the 48 and the 81. A 97 carb flows 155 cfm, the 81 flows 125, and the 48 flows 170.

All the parts to make a 97 are available from Stromberg Carburetor (Stromberg-97.com).

The Stromberg 97 and its variants are the most popular nostalgia hot rod carburetor for multi-carb setups. The advantage to these over the also-common Holley 94s is the brass power valve is mechanical while the 94 uses a vacuum diaphragm. There are a multitude of slight casting differences throughout the run of 97s and their variants, which include the 48 and the 81. A 97 carb flows 155 cfm, the 81 flows 125, and the 48 flows 170.

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Base variations include bore sizes. This shows the standard three-bolt on the center and right carb, but the left one has an uncommon four-bolt flange that won’t work with most aftermarket intake manifolds.

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Besides looking for stripped threads and warped mating surfaces, look for hammer marks and even holes drilled into the tops from past “fixes” for stuck floats. A hole in an otherwise pristine top can be plugged; ball-peen hammer marks, pass. Complete cores go for $100, while gutted 97’s still fetch $50. All the parts to make a 97 are available from Stromberg Carburetor: Stromberg-97.com.

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An “EE 7⁄8” indicates an 81 body.

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Variations in the cast base include a provision, or lack thereof, for a vacuum port (arrow).

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One of the advantages of the Stromberg carbs is the large cast iron base. An “EE-1” designation indicates this base is for a 48 or 97 body.

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The “97” tells you it’s a 97. Some 97s and all 48s won’t have any number castings. In those cases, look inside the air horn for evidence of a choke linkage ball detent to hold the choke open as evidence of a 97. If there’s no provision and the casting is smooth, it’s a 48.

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The “LZ” casting indicates Lincoln-Zephyr and flows 160 cfm. The Lincoln enthusiasts are as crazy as the rest of us, thus pushing the price of these carb cores well above $100. The “81” tells you it’s an 81.

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The “81” tells you it’s an 81.

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Horns can be damaged and are hard to fix. If it looks like this, pass.

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One way to tell what you have is by checking casting marks. The “13⁄16” (arrow) indicates this is an 81 body.

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The “11⁄32” indicates a 48 body; 97 bodies have a “31⁄32” casting designation.

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This shows bad horns on the left and good ones on the right. Also note the difference in castings: the damaged body on the left has cast webs and the right one doesn’t.

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As inlet holes get stripped, they are often rethreaded to a larger size, resulting in less material to tap into. Look for bodies with as much meat around the inlet hole as possible.